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Heat exchangers (HEs) which provide heat transfer and transfer energy through direct or indirect contact between fluids have an essential role in many processes as a part of various industries from pharmaceutical production to electronic devices. Using nanofluid as working fluid and integrating different types of turbulators could be used to upgrade the thermal effectiveness of HEs. Recently, to obtain more increment in thermal effectiveness, hybrid nanofluids are used that are prepared by mixing two or more various nanoparticles. The purpose of this experimental and numerical study is investigating different scenarios for improving the effectiveness of a concentric U-tube type HE.

In the numerical section of this study, different turbulator modifications, including circular and quarter circular rings, were modeled to determine the effect of adding turbulator on thermal performance. In addition, Al₂O₃/water and SiO₂/water single and Al₂O₃–SiO₂/water hybrid nanofluids were experimentally tested in an unmodified concentric U-tube HE in two different modes, including counter flow and parallel flow. Al₂O₃–SiO₂/water hybrid nanofluid was prepared at 2% (wt./wt.) particle ratio and compared with Al₂O₃/water and SiO₂/water single type nanofluids at same particle ratios and with distilled water.

Numerical modeling findings exhibited that integrating turbulators to the concentric tube type HE caused to raise in the effectiveness by improving heat transfer area. Also, experimental results indicated that using both hybrid and single type nanofluids notably upgraded the thermal performance of the concentric U-tube HE. Integrating turbulators cannot be an effective alternative in a concentric U-tube type HE with lower diameter because of raise in pressure drop. Numerically achieved findings exhibited that using quarter circular turbulators decreased pressure drop in comparison with circular turbulators. According to the experimental outcomes, using hybrid Al₂O₃–SiO₂/water nanofluid leads to obtain more thermal performance in comparison with single type nanofluids. The highest increment in overall heat transfer coefficient of HE by using Al₂O₃–SiO₂/water nanofluid achieved as 58.97% experimentally.

The overall outcomes of the current research exhibited the positive impacts of using hybrid nanofluid and integrating turbulators. In this empirical and numerical survey, numerical simulations were performed to specify the impact of applying different turbulators and hybrid nanofluid on the flow and thermal characteristics in a concentric U-tube HE. The achieved outcomes exhibited that using hybrid nanofluid can notably increase the thermal performance with negligible pressure drop in comparison with two different turbulator modifications.

This paper aims to discuss the potentials of interdisciplinary exercises that bring together art and design methodologies in expanding as well as redefining the given methods and principles of basic design in architecture education. The primary purpose is to improve the conventional, well-established principles and methodologies of basic design studios into fresh perspectives.

Focussing on the case study of a basic design studio assignment that translated Richard Serra's Verb List (1967-68) into space-generating operations, the authors analyse how a diagonal interdisciplinary approach to studio pedagogy opened up the basic design studio into the exploration of new concepts and approaches. The assignment encouraged architecture students to productively and creatively engage with a significant art historical work for the purposes of design thinking and exploration.

Findings reveal that the students explored the possible reciprocal influences between materials, actions, and issues of form and organisation, thereby operating in an interface between art, architecture and design surveying the possible interactions between these disciplines. Based on the outcome of this studio exercise, the authors argue that designing assignments that would bring together various and sometimes even conflicting approaches of different fields allow us to reassess and conceptualise anew the pedagogical aims and modi operandi.

The research is original in the ways in which it suggests many possibilities of dialogue, interaction and collaboration between art, design and architecture studios.

Treatment of intersectionality in empirical studies has predominantly engaged with individual categories of difference. The purpose of this paper is to demonstrate that there is utility in exploring intersectionality at the intersection of individual and institutional levels. As such the authors move beyond the polarised take on intersections as either individual or institutional phenomenon and tackle intersectionality as a relational phenomenon that gains meaning at the encounter of individuals and institutions in context. Therefore, the authors explicate how intersectionality features as forms of solidarity and hostility in work environments. As such the authors posit that not only individuals but also the institutions should change if inclusion is aimed at societal and organisational levels.

A thematic analysis on qualitative interview data of a purposive- and snowball-selected sample of 11 lesbian, gay, bisexual, transgender and queer working adults in Turkey was used.

This paper finds evidence to support the existence of a multidimensional model of intersectionality, where conflicting and complementary individual and institutional intersections create four intersectional typologies in the form of intersectional hostility, intersectional struggle, intersectional adjustment and intersectional solidarity.

The extant literature offers rich insights into individual intersectionality but sheds very little light on institutional intersectionality and its interaction with individual intersectionality. This paper attempts to fill in this gap by investigating intersectional encounters as interactions between the individual and institutional intersections.

This study aims to focus on usage of Al₂O₃/water nanofluid as working fluid in a combi boiler. The plate heat exchanger located at the bottom of the combi boiler has been used for heating the domestic water in the present study. Al₂O₃/water nanofluid has also been used in obtaining of the heat energy provided from combustion. Therefore, thermal performance of Al₂O₃/water has been determined by comparing water and nanofluid-water mixture. The present study also investigates heat transfer rates as numerical and experimental for varying cold side outlet temperatures, comparatively.

The present study has included both experimental and numerical methodologies. The experimental setup consists of main heat exchanger, atmospheric burner, circulation pump and plate-type heat exchanger in which the Al₂O₃/water nanofluid was used as working fluid to heat the domestic water. In the numerical part of the study, a commercial computational fluid dynamic code has been used to model heat rate and thermal efficiency of the heat exchanger used.

It has been concluded that the predicted results are in satisfactorily good agreement with the measured data. In the experimental part of the study, the flow rate of Al₂O₃/water nanofluid was kept constant during the experiments. The flow rates of the water by which the heated Al₂O₃/water nanofluid mixture was cooled via the plate heat exchanger have been changed as 3, 4, 5 and 6 lpm. The domestic water temperatures that were kept constant have also been changed as 40°C, 45°C, 50°C, 55°C and 60°C. It has been concluded that the Al₂O₃/water nanofluid thermal efficiency has been 16 per cent better than pure water.

The main originality of the present study is that thermal efficiency of the plate-type heat exchanger when Al₂O₃/water mixture nanofluids are used as there are limited studies related to the usage of Al₂O₃/water mixture nanofluids in the plate-type heat exchanger not only experimental but also numerical methodologies.